A Land grid array electrical connector is normally located between a chip module and a circuit board. Terminals of the electrical connector are electrically conducted with the chip module and the circuit board in a pressing manner. The chip module and the circuit board are provided respectively with conductive sheets which are pressed by the terminals. Because of the structural characteristics of a Land grid array, the terminals of the electrical connector normally have to have good elasticity, which enables the terminals to deform elastically, so that the terminals of the electrical connector can be conducted with the chip module and the circuit board in an elastic pressing manner, and thereby the reliable electrical connection between the chip module and the circuit board can be realized. Further, the terminals also have to have enough pressure resistance to prevent the elasticity of the terminals from decreasing due to long-term pressure.
In order for terminals to have good elasticity, a conventional Land grid array electrical connector terminal, as disclosed in U.S. Pat. No. 6,315,576, is normally provided with a long first elastic suspending arm and a long second elastic suspending arm, and first conductive portions and second conductive portions are arranged respectively at the ends of the suspending arms in order to be respectively in electrical contact with conductive sheets of a chip module and a circuit board. However, since the conductive portions of the electrical connector terminals are located at the ends of the long suspending arms, after the chip module is electrically conducted with the circuit board, a long conductive path which is formed sequentially by the conductive sheet of the chip module, the first conductive portion, the first elastic suspending arm, the second elastic suspending arm and the second conductive portion of the electrical connector terminal and the conductive sheet of the circuit board is formed between the chip module and the circuit board, as a result, the self-inductance effect of the conductive path is great, and moreover, when current flows through the long conductive path, total electrical impedance increases. Since current electrical signal transmission generally has high frequency and will generate a greater self-inductance effect, the normal function of a circuit will be affected due to increases in self-inductance effect and electrical impedance, and thereby the electrical connection between the chip module and the circuit board and signal transmission performance will be affected. Moreover, because the first elastic suspending arm and the second elastic suspending arm are under pressure for a long time, the first elastic suspending arm and the second elastic suspending arm may affect electrical conductivity due to decrease in elasticity.
An existing conductive terminal for socket connectors, as disclosed in a Chinese patent No. 03239559.0, which has solved the above-mentioned technical problems is provided with a mounting portion and an extending portion arranged by extending from one side of a body. The extending portion is U-shaped, and is provided with a first extending portion, a first contacting portion, a second extending portion and a second contacting portion in sequence. The conductive terminal is received in a terminal hole of the insulating body, and the first contacting portion and the second contacting portion respectively protrude and extend out of the two opposite surfaces of the insulating body. When a socket connector is connected with a chip module and a circuit board, each conductive terminal of the socket connector deforms elastically due to pressure applied by the chip module and the circuit board, so that the free end of the second contacting portion moves toward the mounting portion to be in contact with the mounting portion, and thereby a first conductive path, which is formed sequentially by a conductive pad of the chip module, the second contacting portion, the second extending portion, the first contacting portion and a corresponding conductive pad of the circuit board, and a second conductive path, which is formed sequentially by the conductive pad of the chip module, the second contacting portion, the mounting portion, the first extending portion, the first contacting portion and the corresponding conductive pad of the circuit board, are formed. Because the first conductive path and the second conductive path are in a parallel relation, the total impedance value is decreased, consequently, the heat produced by the conductive terminal is reduced during electrical signal transmission, and thereby good electrical conductivity can be provided between the chip module and the circuit board.
However, such a conductive terminal for socket connectors at least has the following disadvantages: since the conductive terminal receives pressure to deform elastically, only after the free end of the second contacting portion is in stable contact with the mounting portion can the second conductive path be formed, and therefore the press-fitting size of the conductive terminal is required to be accurate; if the pressure is too high, it will cause the second contacting portion to deform plastically; if the pressure is not enough, then it will cause the free end of the second contacting portion to be in unstable contact with the mounting portion; as a result, the second conductive path cannot be formed stably, and good electrical conduction cannot be realized between the chip module and the circuit board.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.